Fuel-fired boiler for production of domestic hot water and for heating

ABSTRACT

A boiler has in inner cylindrical vessel through which water is passed for use as a domestic hot water. Surrounding this vessel is a heating chamber containing water and having a downwardly open cup-shaped portion receiving a burner having substantially tangentially directed fuel-expelling orifices. Surrounding the heating chamber is a cylindrical compartment subdivided by a helical member into a helical flow path for the water circulated through a heating system. A flue is provided having a vertical portion extending outside the compartment up through the insulated boiler housing and a horizontal portion passing through the chamber and opening centrally above the burner in the cup shaped lower portion of the chamber. This flue is provided with heat-absorbing ribs, as is the cup-shaped chamber portion, to pick up heat from the burner.

United States Patent Brand] [54] FUEL-FIRED BOILER FOR' PRODUCTION OF DOMESTIC HOT WATER AND FOR HEATING [72] Inventor: Willi Brandl, Schurbungert 12,

8057 Zurich, Switzerland 22 Filed: Jan. 25, 1971 211 App]. No.: 109,300

[30] Foreign Application Priority Data March 25, 1970 Switzerland 4560/70 [52] U.S. Cl....., ..122/33, 122/37 [51] Int. Cl ..F22b 33/02 [58] Field of Search 4122/14, 32, 33, 37

I [56] References Cited I UNITED STATES PATENTS 3,237,608 3/1966 Brandl ..122/33 2,404,860 7/1946 Miller ..122/l4 2,506,336 5/1950 Bock ..l22/14 3,007,457 11/1961 Ospclt ..122/37 [4 1 Dec. 5, 1972 Primary Examiner Kenn eth W. Sprague Attorney-Karl F. Ross [5 7] ABSTRACT- A boiler has in inner cylindrical, vessel through which water is passed for use as a domestic hot water. Surrounding this vessel is a heating chamber Containing water and having a downwardly open cup-shaped portion receiving a burner having substantially tangentially directed fuel-expelling orifices. Surrounding the heating chamber is a cylindrical compartmentsubdivided by a helical member into a helical flow path for the water circulated through a heating system. A tlue is provided having a vertical portion extending outside the compartment up through the insulated boiler housing and a horizontal portion passing through the chamber and opening centrally above the burner in the cup shapedlower portion of the chamber. This flue is provided with heat-absorbing ribs, as is the cupshaped chamber portion, to pick up heat from the burner.

10 Claims, 7 Drawing Figures v PATENTEDBEB 1912 3.704.691

SHEET 3 OF 3 29 I -;1T- 28 I Fig.6 Fig. 7

14a 133 "f f I 13E 4b 8b Willi Brand! Inventor.

by 6R0 0 A! tornay FUEL-FIRED BOILER FOR PRODUCTION OF DOMESTIC HOT WATER AND FOR HEATING FIELD OF THE INVENTION The present invention relates to a boiler and, more particularly, to a boiler used to heat water for domestic use and for house heating.

BACKGROUND OF THE INVENTION OBJECTS OF THE INVENTION It is, therefore, an object of the present invention to provide an improved boiler of the above-mentioned type.

Another object is to provide a boiler responding to the various needs set forth above, i.e. a small, efficient, and trouble-free boiler.

SUMMARY OF THE INVENTION I attain the above objects with a boiler having a closed inner cylindrical vessel through which the water intended for domestic use is passed. A closed heating chamber partially filled with water surrounds the vessel and is provided with a downwardly open cup-shaped portion receiving a burner. Surrounding the heating chamber is a compartment through which the water for use in the heating system is passed. In this manner the heat imparted to the water in the sandwiched chamber is conducted to the water in the vessel and in the compartment. A flue is provided which has an upright portion entirely outside of the vessel, chamber, and compartment, and a horizontal portion passing through the chamber, so that the heat from flue gases can be conducted through its walls to the water in the chamber.

According to another feature of this invention the lower portion of the flue and the interior of the downwardly open cup-shaped portion of the chamber are provided with heat-conductive ribs adapted to pick up heat from the burner.

In accordance with yet another feature of this invention the burner is a ring provided with a plurality of outwardly opening peripheral fuel-expelling nozzles or orifices which do not open directly radially, but open generally tangentially. According to a further feature of the present invention these orifices open at an angle of around 45 to tangents of the burner ring at the orifice.

DESCRIPTION OF THE DRAWING The above and other objects, features and ad vantages will become apparent from the following description, reference being made to the accompanying drawing in which:

FIG. I is a vertical section through the boiler according to the present invention;

FIG. 2 is a section taken along line I] II of FIG. 1., and

FIGS. 3 to 7 are vertical sectional views through details of second and other embodiments of the present invention.

SPECIFIC DESCRIPTION As shown in FIGS. 1 and 2, a boiler has a'heating chamber 1 with a steel cylindrical wall 2 and a downwardly open cup-shaped bottom wall 3 forming the floor of this chamber and a top 4. Within this chamber 1 is a vessel 5 formed by a cylindrical steel wall 6 and inwardly concave top and bottom walls 8 and 7, respectively. The top 4 of the chamber 1 and the top 8 of the vessel 5 in this embodiment are the same concave metal disk. Surrounding the upper portion 9 of the chamber 1 is a compartment defined by a cylindrical steel wall 10. A wire 11 having a diameter of about 6 to 8 millimeters extends helically down between the walls 9 and 10 while engaging both of these walls to define a helical flow path 12 therebetween. The wall 10 extends up beyond the wall 9 and is upwardly closed by a top wall 13 so that the compartment formed by the walls 9, 10 and 13 is cup shaped and downwardly open over the upper region of the heating chamber 1. A return conduit 14, in which a circulating pump 15 is provided, extends through the wall 13, and another conduit 16 is provided at the base of the path 12 so that water passes over the top of the vessel 5 and then helically down around the sides of the chamber 1 as it is heated.

Both of the top walls 8 and 13 are formed with respective in-line central circular openings 17 and 18 and a ring 19 is welded to the inside of these openings. A cover 20 is bolted to the ring 19 by screws 21 (FIG. 2) and feeds a pair of conduits 22 and 23 into the vessel 5. The conduit 22 has, at one end, along vertical extension 25 opening into the base of the vessel 5 with a funnel-shaped disperser 26 and is connected at its other end to a conduit 24 coupled to a fresh-water-supply. The other'conduit 23 merely opens at the top of the vessel 5 and is connected to a conduit 27 which leads to the domestic hot-water system. In this manner, fresh cold water is drawn into the base of the vessel 5 as hot water is drawn out the top, with this water being heated as it rises.

The heating chamber 1 has an interior 28 whose upper region 29 is evacuated and whose lower region 30 extending as a web across the boiler and region 31 extending downwardly from this web 30 are filled with water. The water level 32 is maintained with the aid of a gauge and a water line 47, so that if the level drops below the level 32 water can be admitted and if it goes above the level 32 water can be drawn off through the pipe 47. An expansion chamber 38 is provided which is connected to the path 12.

A flue having a horizontal lower portion 33, fully below the water level 32, passing through the region 30 opens centrally at 34 into a burning chamber 35. This flue also has a vertical portion 36 entirely outside of the outer compartment and extending up within the boiler housing 37 which is internally lined with thermal insulation 49. A plurality of horizontal portions 44' can also be provided as shown in FIG. 5.

The entire heating chamber 1 rests on a circular base 39. A burner ring 40 is provided in the combustion chamber 35 above the lower end of the region 31. This burner is provided with a plurality of peripheral fuel (gas or oil) nozzles 41 each directed at an angle a of 45 to a respective imaginary tangent of the circular burner ring 40. The flames 42 formed by these outlets thus make a spiralling vortex. The cup-shaped lower region of the chamber 1 has a height above the burner corresponding substantially to the burner radius, so that an excellent heat pickup is possible by the water in this chamber. For even better heat exchange, ribs 43 are provided on the base of the web 30 and inclined to the direction 50 of gas flow in the chamber 35. Similarly, longitudinally extending ribs 44 are provided in the lower flue portion 33 so that the maximum amount of heat is picked up from the flue gases and passed to the water in the heating chamber.

Since the heating chamber is closed, the water in it can be heated up very close to and even somewhat beyond the boiling point if desired. A thermostat set at, say 85 C. in the inner vessel Swould control the burner 40, while the pump 15 would be controlled by a room wall thermostat. The water in the heating chamber vaporized and rises, then it condenses, giving up its heat to the water in the vessel and in the path 12.

FIG. 3 shows an alternative embodiment wherein the heating chamber fully surrounds the vessel 5. In this case the top wall 8a of the vessel 5 and the top wall 4a of the heating chamber 1 are spaced apart and the wall 40 extends at 13a out to the wall 10. FIGS. 6 shows how in such an embodiment a pair of parallel member 11 and 11'' are provided which subdivide the compartment between the walls and 9 into a pair of parallel helical paths l2 and 12". A lateral inlet 14a for the heating water is provided in these embodiments.

in FIG. 4 there is shown a boiler which is not doublewalled at its top, but wherein the walls 4b, 8b and 13b of the vessel, chamber and compartment areall the same body. FIG. 7 shows how in this embodiment the chamber between the walls 9 and 10 is subdivided by a horizontal wall 48. An inlet l4b',l4b" is provided at the top of each portion defined by the wall 48 and a lower outlet 16' for the upper portion is shown. Such a system is useful where a pair of totally independent heating networks are needed. It is, of course, possible to separate the two helical paths 12 and 12" of FIGS for use in independent networks by forming the upper boiler wall as in FIG. 4 and providing the necessary pairs of outlets and inlets.

It is also possible to install heating coils in the upper region 29 of the steam chamber 28 in series with the flow path 12 for use in extremely hot heating systems where water above 100 C. is used.

lclaim:

l. A boiler comprising:

a closed vessel;

means for passing water for domestic use through said closed vessel;

a closed chamber surrounding the sides and base of said vessel and havinga downwardly open cupshaped portion below said vessel and forming a floor of said chamber, the cup cavity of said portion being located externally of said chamber;

means defining a substantially cylindrical compartment at least partially surrounding said chamber;

means for passing heating water through said compartment;

a helical member defining a helical flow path centered on a vertical axis in said compartment.

2. The boiler defined in claim 1 wherein said chamber and said vessel are substantially cylindrical and said compartment is cup shaped with said helical member defining said path in the sides ofsaid compartment, said means for passing heating water through said compartment comprising an inlet at the top of said compartment and an outlet at the lower end of sai helical flow path. i

3. The boiler defined in claim 1 wherein said chamber and said vessel are substantially cylindrical and said chamber completely surrounds said vesseh 4. The boiler defined in claim 1 wherein said burner means includes an annular burner having a plurality of peripheral fuel-expelling orifices directed substantially tangentially outwardly to form a spiralling flame within said cup-shaped lower portion of said chamber.

5. The boiler defined in claim 5 wherein said orifices are each directed at around 45 to a tangent of said burner. 1

6. The boiler defined in claim 1 wherein said downwardly open cup-shaped portion of said chamber is provided with heat-conducting ribs exposed to said burner means.

7. The boiler defined in claim 1 whereinsaid flue is provided at least at said horizontal lower portion with heat-conducting ribs adapted to pick up heat from flue gases.

8. The boiler defined in claim 1 wherein said means for passing water for domestic use includes a feedthrough collar at the top of said vessel and an inlet conduit and an outlet conduit extending through said collar into said vessel, said boiler being double-walled at the top with one of the walls constituted by said vessel and said collar passing through and welded to both walls.

9. The boiler defined in claim 1, further comprising a housing surrounding said vessel, chamber and compartment, and thermal insulation lining said-housing.

10. A boiler comprising:

a closed vessel:

means for passing water for domestic use through said closed vessel;

a closed chamber surrounding the sides and base of said vessel and having a downwardly open cup shaped portion below said vessel and forming a floor of said chamber, the cup cavity of said portion being located externally of said chamber;

means defining a substantially cylindrical compartment at least partially surrounding said chamber;

means for passing heating water through said compartment',

burner means under said downwardly open cupshaped portion for heating water in said chamber and thereby conductively heating water in said vessel and in said compartment; and

a flue for leading off exhaust vapors from said burner cup-shaped lower portion of said chamber, said downwardly open cup-shaped portion of said chamber being provided with heat-conducting ribs exposed to said burner means, said flue being provided at least at said horizontal lower portion with heat-conducting ribs adapted to pick up heat from flue gases. 

1. A boiler comprising: a closed vessel; means for passing water for domestic use through said closed vessel; a closed chamber surrounding the sides and base of said vessel and having a downwardly open cup-shaped portion below said vessel and forming a floor of said chamber, the cup cavity of said portion being located externally of said chamber; means defining a substantially cylindrical compartment at least partially surrounding said chamber; means for passing heating water through said compartment; burner means under said downwardly open cup-shaped portion for heating water in said chamber and thereby conductively heating water in said vessel and in said compartment; a flue for leading off exhaust vapors from said burner means and having a horizontal lower portion traversing said chamber and a vertical upper portion, said lower portion having walls in heat-conducting engagement with the water in said chamber; and a helical member defining a helical flow path centered on a vertical axis in said compartment.
 2. The boiler defined in claim 1 wherein said chamber and said vessel are substantially cylindrical and said compartment is cup shaped with said helical member defining said path in the sides of said compartment, said means for passing heating water through said compartment comprising an inlet at the top of said compartment and an outlet at the lower end of said helical flow path.
 3. The boiler defined in claim 1 wherein said chamber and said vessel are substantially cylindrical and said chamber completely surrounds said vessel.
 4. The boiler defined in claim 1 wherein said burner means includes an annular burner having a plurality of peripheral fuel-expelling orifices directed substantially tangentially outwardly to form a spiralling flame within said cup-shaped lower portion of said chamber.
 5. The boiler defined in claim 5 wherein said orifices are each directed at around 45* to a tangent of said burner.
 6. The boiler defined in claim 1 wherein said downwardly open cup-shaped portion of said chamber is provided with heat-conducting ribs exposed to said burner means.
 7. The boiler defined in claim 1 wherein said flue is provided at least at said horizontal lower portion with heat-conducting ribs adapted to pick up heat from flue gases.
 8. The boiler defined in claim 1 wherein said means for passing water for domestic use includes a feed-through collar at the top of said vessel and an inlet conduit and an outlet conduit extending through said collar into said vessel, said boiler being double-walled at the top with one of the walls constituted by said vessel and said collar passing through and welded to both walls.
 9. The boiler defined in claim 1, further comprising a housing surrounding said vessel, chamber and compartment, and thermal insulation lining said housing.
 10. A boiler comprising: a closed vessel: means for passing water for domestic use through said closed vessel; a closed chamber surrounding the sides and base of said vessel and having a downwardly open cup-shaped portion below said vessel and forming a floor of said chamber, the cup cavity of said portion being located externally of said chamber; means defining a substantially cylindrical compartment at least partially surrounding said chamber; means for passing heating water through said compartment; burner means under said downwardly open cup-shaped portion for heating water in said chamber and thereby conductively heating water in said vessel and in said compartment; and a flue for leading off exhaust vapors from said burner means and having a horizontal lower portion traversing said chamber and a vertical upper portion, said lower portion having walls in heat-conducting engagement with the water in said chamber, said burner means including an annular burner having a plurality of peripheral fuel-expelling orifices directed substantially tangentially outwardly to form a spiralling flame within said cup-shaped lower portion of said chamber, said downwardly open cup-shaped portion of said chamber being provided with heat-conducting ribs exposed to said burner means, said flue being provided at least at said horizontal lower portion with heat-conducting ribs adapted to pick up heat from flue gases. 